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Disc Rotor Upgrade

SikoraSikora Posts: 519
edited July 2008 in MTB buying advice
I want to upgrade the front disc on my bike as i feel as if my brakes are powerful enough with a 160mm rotor (Brakes are Juicy Three's)

I only really ride at trail centres, but i'm quite a burly lad (16.5 st to be exact)
Now, would i benefit more from a 203mm rotor? Or will a 185mm be sufficiant?
Are there any side affects from running such a large rotor up front?

I don't want to spend £30 or whatever on a 185mm rotor to find its not much different to the 160mm, and at the sime time i don't want to fit a 203mm if its going to make me lock the brake too easily

Just searching the Rockshox website to see if my Reba SL's can actually use a 203mm rotor........


  • S_J_PS_J_P Posts: 908
    RS Reba SL's are okay for 203mm rotors, but I'd suggest that a 185mm rotor will be sufficient. I went the 8" route, and it's a bit big and burly and over the top for what's in effect an XC bike.

    Are you getting a rotor-kit complete with rotor and adapter, or are you going the DIY route sourcing the rotor and a +20mm adapter (for 185mm) yourself?
  • SikoraSikora Posts: 519
    Was just going to buy a new rotor and adaptor from CRC. Secondhand ones don't seem to come up much cheaper on eBay.

    i take it this is the adaptor i need for a 185mm rotor on a Reba fork?:
  • BleedproofBleedproof Posts: 107
    Yeah..thats the one....

    So you decided against the Carbons? I went for the Ultimate 185mm in the end and have yet to fit them but they look great

  • shin0rshin0r Posts: 555
    Bigger the better in my opinion - go for the 203s
  • ride_wheneverride_whenever Posts: 13,279
    Control is good, go for 185mm
  • ride_wheneverride_whenever Posts: 13,279
    Control is good, go for 185mm
  • xtremedashxtremedash Posts: 182
    I have Juicy 3's with a 203mm rotor on the front of my Pitch, I'm not especially big (<12st), but do tend to ride very hard then grab a lot of brake at the last minute.

    I have found on a couple of occasions that the front will lock if I'm not careful. There's also not masses of modulation on the 3's, so you have to have a pretty good feel for the brakes so as not to through yourself off.
    If you're not living life on the edge, you're taking up too much room!
  • S_J_PS_J_P Posts: 908
    I'm heavy, and I still think 8" is too big for XC. It also puts a hell of extra strain on the mounts.

    185mm will be plenty big enough, it gives a 15% increase in diameter and thus braking force, and aids heat dissipation, and isn't OTT.
  • SikoraSikora Posts: 519
    Thanks for the advice guys. 185mm rotor is on its way
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